| /* |
| * |
| * Copyright 2023 gRPC authors. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| */ |
| |
| package serviceconfig |
| |
| import ( |
| "encoding/json" |
| "fmt" |
| "math" |
| "strconv" |
| "strings" |
| "time" |
| ) |
| |
| // Duration defines JSON marshal and unmarshal methods to conform to the |
| // protobuf JSON spec defined [here]. |
| // |
| // [here]: https://protobuf.dev/reference/protobuf/google.protobuf/#duration |
| type Duration time.Duration |
| |
| func (d Duration) String() string { |
| return fmt.Sprint(time.Duration(d)) |
| } |
| |
| // MarshalJSON converts from d to a JSON string output. |
| func (d Duration) MarshalJSON() ([]byte, error) { |
| ns := time.Duration(d).Nanoseconds() |
| sec := ns / int64(time.Second) |
| ns = ns % int64(time.Second) |
| |
| var sign string |
| if sec < 0 || ns < 0 { |
| sign, sec, ns = "-", -1*sec, -1*ns |
| } |
| |
| // Generated output always contains 0, 3, 6, or 9 fractional digits, |
| // depending on required precision. |
| str := fmt.Sprintf("%s%d.%09d", sign, sec, ns) |
| str = strings.TrimSuffix(str, "000") |
| str = strings.TrimSuffix(str, "000") |
| str = strings.TrimSuffix(str, ".000") |
| return []byte(fmt.Sprintf("\"%ss\"", str)), nil |
| } |
| |
| // UnmarshalJSON unmarshals b as a duration JSON string into d. |
| func (d *Duration) UnmarshalJSON(b []byte) error { |
| var s string |
| if err := json.Unmarshal(b, &s); err != nil { |
| return err |
| } |
| if !strings.HasSuffix(s, "s") { |
| return fmt.Errorf("malformed duration %q: missing seconds unit", s) |
| } |
| neg := false |
| if s[0] == '-' { |
| neg = true |
| s = s[1:] |
| } |
| ss := strings.SplitN(s[:len(s)-1], ".", 3) |
| if len(ss) > 2 { |
| return fmt.Errorf("malformed duration %q: too many decimals", s) |
| } |
| // hasDigits is set if either the whole or fractional part of the number is |
| // present, since both are optional but one is required. |
| hasDigits := false |
| var sec, ns int64 |
| if len(ss[0]) > 0 { |
| var err error |
| if sec, err = strconv.ParseInt(ss[0], 10, 64); err != nil { |
| return fmt.Errorf("malformed duration %q: %v", s, err) |
| } |
| // Maximum seconds value per the durationpb spec. |
| const maxProtoSeconds = 315_576_000_000 |
| if sec > maxProtoSeconds { |
| return fmt.Errorf("out of range: %q", s) |
| } |
| hasDigits = true |
| } |
| if len(ss) == 2 && len(ss[1]) > 0 { |
| if len(ss[1]) > 9 { |
| return fmt.Errorf("malformed duration %q: too many digits after decimal", s) |
| } |
| var err error |
| if ns, err = strconv.ParseInt(ss[1], 10, 64); err != nil { |
| return fmt.Errorf("malformed duration %q: %v", s, err) |
| } |
| for i := 9; i > len(ss[1]); i-- { |
| ns *= 10 |
| } |
| hasDigits = true |
| } |
| if !hasDigits { |
| return fmt.Errorf("malformed duration %q: contains no numbers", s) |
| } |
| |
| if neg { |
| sec *= -1 |
| ns *= -1 |
| } |
| |
| // Maximum/minimum seconds/nanoseconds representable by Go's time.Duration. |
| const maxSeconds = math.MaxInt64 / int64(time.Second) |
| const maxNanosAtMaxSeconds = math.MaxInt64 % int64(time.Second) |
| const minSeconds = math.MinInt64 / int64(time.Second) |
| const minNanosAtMinSeconds = math.MinInt64 % int64(time.Second) |
| |
| if sec > maxSeconds || (sec == maxSeconds && ns >= maxNanosAtMaxSeconds) { |
| *d = Duration(math.MaxInt64) |
| } else if sec < minSeconds || (sec == minSeconds && ns <= minNanosAtMinSeconds) { |
| *d = Duration(math.MinInt64) |
| } else { |
| *d = Duration(sec*int64(time.Second) + ns) |
| } |
| return nil |
| } |